Method and apparatus for manufacturing combination shock absorbers and leveling struts

ABSTRACT

A method and apparatus for assembling combination shock absorbers and leveling struts of the type comprising a telescopic direct acting shock absorber having a reciprocable piston and piston rod, with the piston rod carrying a cylindrical dirt shield which cooperates with a rolling or flexible diaphragm member extending between the body of the shock absorber and the dirt shield in defining a variable volume pressurizable chamber. The dirt shield is displaced relative to the shock absorber in response to the magnitude of pressure maintained in the chamber whereby to selectively control the attitude between sprung and unsprung portions of a vehicle. The method and apparatus of the present invention includes means for initially inserting one end of the diaphragm around the body of the shock absorber for selectively gauging the axial location thereon and thereafter for crimping a suitable clamping ring around the outer periphery of one end of the diaphragm so as to fixedly and sealingly secure the one end to the body of the shock absorber. means are then provided for selectively inverting an opposite end of the diaphragm, for sleeving the same over the adjacent end of the dirt shield, and for pressurizing the unit so as to properly axially position the diaphragm with respect to the dirt shield. In this position, the opposite end of the diaphragm is clampingly secured to the end of the dirt shield, whereby the diaphragm and dirt shield will cooperate with the body of the shock absorber in defining the aforesaid pressurizable chamber.

SUMMARY OF THE INVENTION

The present invention relates generally to vehicular shock absorbers ofthe type which utilizes a pressurizable chamber adapted to beselectively pressurized in order to effect a leveling of the sprungportion of a vehicle with respect to the unsprung portion thereof. Moreparticularly, the present invention is directed toward a new andimproved method and apparatus for assembling such combination shockabsorbers and leveling struts, whereby a minimum number of manufacturingsteps are required so that the unit may be manufactured in an extremelysimple and economical manner.

It is accordingly a general object of the present invention to provide anew and improved method and apparatus for assembling combination shockabsorber and leveling struts for use in automotive vehicles and thelike.

It is a more particular object of the present invention to provide a newand improved method for assembling combination shock absorbers andleveling struts, as above described, which minimizes to the extreme thenumber of successive operational steps and which provides a wellconstructed, reliable unit.

It is another object of the present invention to provide a new andimproved method, as above described, which assures for close qualitycontrol and which utilizes a minimum amount of tooling and relatedmanufacturing equipment.

It is still another object of the present invention to provide a new andimproved apparatus for assembling combination shock absorbers andleveling struts, which apparatus is adapted to fixedly and sealinglysecure the opposite ends of the flexible diaphragm to the body of theshock absorber and associated dirt shield, respectively.

It is a related object of the present invention to provide a new andimproved means for selectively sleeving one end of the diaphragm overthe outer periphery of the adjacent end of the dirt shield in a rapidand effective manner which assures for positive sealing engagementtherebetween.

It is a further object of the present invention to provide a new andimproved method for assembling flexible diaphragms on the dirt shield ofcombination shock absorbers and leveling struts wherein one end of thediaphragm is selectively positioned with respect to the associated dirtshield in response to introducing a pressurized media in the variablevolume chamber.

Other objects, features and advantages of the present invention willbecome apparent from the following detailed description taken inconjunction with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a side elevational view with parts broken away of an exemplarycombination shock absorber - leveling strut which is adapted to bemanufactured in accordance with the method and apparatus of the presentinvention;

FIGS. 2-7 are a sequential series of side elevational views of the shockabsorber-leveling unit illustrated in FIG. 1 depicting the various stepsof assembly in accordance with the preferred method of the presentinvention;

FIG. 8 is a sectional side elevation of a preferred apparatus forcrimply attaching the clamping rings in accordance with the steps of themethod illustrated in FIGS. 4 and 7;

FIG. 9 is an end view of the apparatus illustrated in FIG. 8 looking inthe direction of the arrow 9;

FIG. 10 is a fragmentary transverse cross-sectional view of theapparatus illustrated in FIG. 8 taken along the lines 10--10 thereof;

FIG. 11 is a fragmentary plan view of the apparatus illustrated in FIG.8 looking in the direction of the arrow 11;

FIG. 12 is a side elevational view of a preferred apparatus forinverting the flexible diaphragm and for sleeving one end thereof to thedirt shield in accordance with the step of the method illustrated inFIG. 5;

FIG. 13 is a top or plan view of the lower end of the apparatusillustrated in FIG. 12 looking in the direction of the arrow 13;

FIG. 14 is a top or plan view of a fixture adapted to axially locate thereturn bend of the flexible diaphragm relative to the dirt shield of theleveling strut in accordance with the step of the method alsoillustrated in FIG. 5; and

FIG. 15 is a side elevational view of the fixture illustrated in FIG.14.

DETAILED DESCRIPTION OF THE INVENTION

Referring now in detail to the drawings and in particular to FIG. 1thereof, a combination shock absorber-leveling unit or strut 10 which isadapted to be constructed in accordance with the method and apparatus ofthe present invention, is adapted to be operatively mounted betweensprung and unsprung masses of an automotive vehicle or the like insubstantially the same location that a conventional shock absorbernormally occupies adjacent each of the suspension spring means of thevehicle. Accordingly, the unit 10 is adapted to function solely as ashock absorber to dampen relative movement between the sprung andunsprung masses when an associated variable volume chamber is notpressurized. However, in response to pressurizing the chamber to somepre-determined magnitude, the unit elongates to displace the sprung massrelative to the unsprung mass whereby to optimize the stabilization ofthe vehicle and achieve relatively level vehicular attitude, as will beappreciated by those skilled in the art. The strut 10 may be of variousconstructions well known in the art and for purposes of description, isshown generally as comprising a direct acting tubular shock absorberassembly 12. The assembly 12 includes an external cylindrically shapedreserve tube or body member 14 which is closed at the upper and lowerends thereof by suitable end cap members 16 and 18, respectively. Thelower cap member 18 is provided with a conventional mounting ring orsimilar attachment element 20 which is designed to be operativelysecured to the unsprung mass of the associated vehicle, such as by wayof example, to the axle assembly thereof. Disposed interiorly of thebody member 14, is an elongated cylindrical pressure cylinder 22, theupper end of which is provided with guide means 24 defining a bore 26within which an elongated piston rod 28 is reciprocally mounted. Thelower end of the piston rod 28 is operatively connected to a pistonassembly, generally designated by the numeral 30 which may be of anysuitable construction well known in the art which is provided withconventional compression and rebound control valves or the like (notshown). The annular space between the outer periphery of the reservetube 14 defines a fluid reservoir 32 which is adapted to containhydraulic fluid which cooperates with the valves of the piston indamping movement of the sprung portion of the associated vehicle withrespect to the unsprung portions thereof.

The unit 10 also comprises a generally cup shaped enclosure member ordirt shield 36, having a skirt section 38 arranged coaxially of theshock absorber assembly 12 and spaced radially outward therefrom. Thebase of the shield 36 is formed by an upper end cap 40 which is fixedlysecured to the piston rod 28 and carries a suitable upper attachmentring or element 42 adapted to be secured to the sprung portion of theassociated vehicle, as is conventional in the art. The opposite end ofthe shield 36 is connected to the shock absorber 12 by an elongated,generally tubular shaped diaphragm member, generally designated by thenumeral 44. The member 44 is fabricated of a flexible material, such asmolded rubber or the like which may, if desired, be reinforced with asuitable fabric for purposes of reinforcement. The member 44 cooperateswith the inner periphery of the dirt shield 36 and the outer peripheryof the reserve tube 14 is defining an enclosed pressurizable chamber 46into which pressurized gas, such as compressed air or the like, isadapted to be supplied from a source via a suitable valve assembly 48supported by a threaded nipple 47 connected to the dirt shield 36. Thediaphragm member 44 comprises a generally cylindrically disposed innerwall section 50 and a generallly cylindrically shaped outer wall section52 which are interconnected by an integral return bend section 54, withthe section 54 being composed of relative portions of the wall sections50 and 52 as reciprocation occurs between the reserve tube 14 and thedirt shield 36. The outer wall section 52 comprises a free end portion56 which is adapted to be fixedly clampingly secured around the outerperiphery of the lower end of the dirt shield 36 by means of a clampingring 58, while the inner wall section 50 comprises a free end portion 60which is adapted to be fixedly secured by means of a clamping ring 62 tothe outer periphery of the upper end of the body member 14, with theclamping rings 58 and 62 serving to provide a fluid tight seal at theopposite ends of the diaphragm 44 to facilitate selective pressurizationof the chamber 46 and correspondingly elongation of the unit 10.

The subject invention is addressed to a method and apparatus forassembling a combination shock absorber-leveling strut 10 of the abovecharacter. The present invention, however, is not intended to in any waybe limited to the specific exemplary unit shown in FIG. 1 and it will beappreciated that the above description is presented merely to describean exemplary embodiment of a typical combination shock absorber-levelingstrut which may be advantageously constructed in accordance with themethod and apparatus of the present invention.

As will hereinafter be described in detail, the subject inventionpertains to a method for assembling opposite ends of the diaphragm 44 tothe dirt shield 36 and the reserve tube 14. Moreover, to facilitate theassembly of the combination shock absorber-leveling strut 10 inaccordance with the various steps of the method, the present inventionalso includes the apparatus for performing the steps such as, forexample, the machine for crimping the clamping rings 58 and 62 to thedirt shield 36 and reserve tube 14 respectively, the apparatus forinverting and subsequently sleeving the diaphragm 44 around the open endof the shield 36 and the fixture for axially locating the rolled orreturn bend 54 of the diaphragm 44 relative to the open end of the dirtshield 36. Generally speaking, and in accordance with the method ofmanufacture of the subject invention, the combination shockabsorber-leveling strut 10 is assembled by a method which comprises thesteps of initially inserting one end of the diaphragm around the reservetube 14 of the assembly 12, selectively gauging the axial location ofthe diaphragm 44 relative to the reserve tube 14 and the clamping ring62 relative to the dirt shield 36, crimping the clamping ring 62 aroundthe outer periphery of the diaphragm 44, inverting an opposite end ofthe diaphragm 44 and sleeving the same over the adjacent end of the dirtshield 36, pressurizing the chamber 46 to properly axially position thereturn bend 54 of the diaphragm 44 with respect to the open end of thedirt shield 36, and crimping the clamping ring 58 to secure the oppositeend of the diaphragm 44 to the dirt shield 36. The above indicated stepsare illustrated in sequence in FIGS. 2-7 of the drawings.

With reference to FIG. 2, the shock absorber 12 including the dirtshield 36 and the mounting or attachment rings 20 and 42, are initiallypreassembled, the fluid reservoir 32 is fully charged with a hydraulicliquid and the piston assembly 30, which carries the dirt shield 36, isdisposed in its furthest axially elongated position. For the purpose oflocating and connecting opposite end sections of the diaphragm 44 inpredetermined axial location relative to the shock absorber 12, theclamping ring 62 is precisely located relative to the reserve tube 14.Correspondingly, the clamping ring 58 also is precisely located relativeto the dirt shield 36. As shall hereinafter be more fully described, themethod of assembly further encompasses crimpingly connecting each of theclamping rings 58 and 62 to the shock absorber 12, whereby to fixedlysecure opposite ends of the diaphragm 44 to the reserve tube 14 and thedirt shield 36 respectively.

The sequence of assembly initially includes the step of telescopicallyinserting the diaphragm 44 around the body of the reserve tube 14 in amanner to selectively gauge the axial location of the relative endportions thereof, including axial placement of the clamping ring 62 in apreselected location on the reserve tube 14. In this regard, and withreference to FIG. 3, the clamping ring 62 is initially preassembledabout the outer periphery of the diaphragm 44. To facilitate thepreassembly, the upper end of the diaphragm 44 is provided with anaxially extending tapered section 68, the crown of which is adapted toroughly position the ring 62 relative to the diaphragm 44. The diaphragm44, including the clamping ring 62, is then slidably inserted on thereserve tube 14 and precisely positioned relative to a preselectedreference surface as can be provided by an exemplary gauge means 70. Byway of example, the gauge means 70 can be provided with a recess 72dimensioned to receive the mounting ring 20 and can include a lower wall74 which is selectively spaced below an annular shaped shoulder 75. Thewall 74 and shoulder 75 can be utilized as reference points in locatingthe lower end of the diaphragm 44 relative to the reserve tube 14. Notethat when the lower surface of the mounting ring 20 engages the wall 74,the diaphragm 44 will be precisely and preselectively axially locatedrelative to the reserve tube 14 in accordance with the preselectedspacing. Moreover, a suitable gauge means 76, having a gauging finger78, can be provided for axially locating the clamping ring 62 apreselected axial distance from the lower or open end of the dirt shield36. In this position, the step of crimping the ring 62 in accordancewith the step of the method illustrated in FIG. 4 can be accomplishedwhereby the end of the diaphragm 44 can be fixedly and sealinglyconnected to the reserve tube 14 and form an annularly shaped recess 64thereabout.

The crimping step, as illustrated in FIG. 4, is performed by anapparatus comprising a crimping machine and a supporting fixture whichare indicated generally at 80 and 82 respectively in FIGS. 8 and 9 ofthe drawings. The machine 80 is comprised of a support structure 84 ofpreferably welded construction, a crimping mechanism 104, and a powercylinder 106 drivingly connected to the mechanism 104. The structure 84includes a base member 86 which is fixedly connected to a top surface 88of a suitable work table or the like by a plurality of suitable fastenermeans 90. The right end of the member 86, as viewed in FIG. 8, isconnected to the lower end of an upwardly extending end wall 92, thelatter including an enlarged cylindrically shaped opening or passage 94adapted to receive an end section of a tubular shaped sleeve element 96.The opposite end of the element 96 is disposed in an identically formedopening 98 located in a mounting plate 100. In a preferred construction,the mounting plate 100 and end wall 92 are connected by one or morelongitudinally extending web sections 102.

In the subject invention, the crimping mechanism 104 is actuated inresponse to displacement of the power cylinder 106. The cylinder 106 ismounted on the end wall 92 by a plurality of suitable bolts, screws orthe like 108 and selectively axially spaced therefrom by stop and spacerelements 110 and 112 respectively. The stop element 110 is connected tothe end wall 92 by a plurality of bolts, screws or the like 114, andincludes a radially extending shoulder 116 disposed in an internal,cylindrially shaped opening or passage 118 which functions as a locatormeans for precisely limiting the inward movement of the jaws or dies ofthe crimping mechanism 104, as will hereinafter be described in detail,whereas the spacer element 112 permits coaxial alignment of the cylinder106 relative to the axis of the sleeve 96. Preferably, the shoulder 116and the spacer element 112 are ground flush after assembly of themechanism 80 whereby to align the cylinder 106 and to preset the inwardposition of each of the jaws or dies.

The power cylinder 106 includes a stub shaft 120 having an outerthreaded section 122 which is drivingly connected to the right end of anelongated, tubular shaped shaft 124. The shaft 124 is non-rotatablysecured relative to the stub shaft 120 by a roll pin 126 which isengaged in aligned apertures formed in each of the shafts 120 and 124.Correspondingly, to preclude relative rotational movement between thesleeve 96 and the shaft 124, the latter is provided with an axiallyextending groove or recess 128 which is formed in the outer peripheralsurface thereof. The groove 128 is engaged by an end section of alocator pin 130, an opposite end of the pin being supported in athreaded aperture 131 extending through each of the walls of the sleeve96 and a cap member 133. In the subject mechanism 80, the sleeve 96functions to slidably support the shaft member 124 which in turn isutilized for engageably receiving and guiding one end of the combinationshock absorber-leveling strut 10. To slidably support the shaft 124, apair of cylindrically shaped bearing sleeves or liners 132 and 134 arelocated at opposite ends of the sleeve 96. With respect to the guidemeans for engageably receiving the combination unit 10, a pair ofcircumferentially spaced roller elements 132 and 134 are rotatablysupported in the lower left end of the shaft member 124.

An enlarged cylindrically shaped cavity 136 is formed circumjacentlyabout the left end of the shaft 124 wherein a connecting means islocated to translate the reciprocal motion provided by the powercylinder 106 whereby to actuate the crimping mechanism 104. Themechanism 104 is carried on the left or outer surface of the mountingplate 100 and fixedly connected to one axial end by a plurality of boltsor cap screws, one of which is indicated at 138. The mechanism 104includes an outer housing formed by an enlarged, ring shaped housingmember 140 which is connected at an opposite axial end to a guide plate142. The left or outer surface of the guide plate 142 is provided with aplurality of circumferentially spaced, radially extending grooves 144,each groove 144 being adapted to slidably support a generallyrectangularly shaped slide member 146 (see FIG. 11).

In the subject apparatus, each of the slide members 146 are radiallydisplaced in response to axial movement of the shaft 124 through adriving connection provided by a plurality of bell cranks 152, thenumber of cranks corresponding to the number of slide members 146. Eachof the bell cranks 152 are substantially L-shaped and each are supportedfor pivotal movement by a bifurcated or U-shaped bracket 154. As bestseen in FIG. 10, each of the bell cranks 152 are located or interposedbetween parallel spaced side sections 156 and 158 of the bracket 154 andpivotably connected thereto by a suitable connecting pin or rod 160, theconnection preferably including a suitable lube fitting 162 or the like.Each of the side sections 156 and 158 project outwardly and to the leftrelative to a generally rectangularly shaped base portion 164, thelatter being preferably connected by welding to the mounting plate 100.Each of the bell cranks 152 comprise a first arm section 166 having acamming surface 168 located in a recess 136 formed in the shaft 124, anda second arm 170 extending through a passageway 148 formed in the plate142, the arm 170 having a camming surface 172 disposed in arectangularly shaped groove 150 formed in the slide member 146.Accordingly, in response to displacement of the shaft 124, to the leftas viewed in FIG. 8, the plurality of bell cranks 152 are subject topivot in a clockwise direction whereby to urge the slide members 146radially outward relative to the central longitudinal axis of the shaft124. Conversely, as the shaft 124 is drivingly displaced to the right,the bell cranks 152 are subject to pivot in a counterclockwise directionwhereby to displace the slide members 146 inwardly in a radialdirection, (i.e., towards the central longitudinal axis of the shaft124). As best seen in FIG. 11, each of the slide members 146 includelaterally extending flange or guide sections 174 and 176, the innersurface of which abuts against the left or outer surface of the guideplate 142. Each of the members 146 are slidably retained in the grooves144 by a circularly shaped stay or retainer plate 178, the latter beingfixedly connected to the outer surface of the guide plate 142 by aplurality of bolts or cap screws indicated generally in FIG. 9 at 180.

In the subject invention, the slide members 146 are each adapted tooperatively support a die or crimping finger element 184. The elements184 are detachably connected to the members 146 by suitable bolts,screws or the like 186 and selectively aligned and positioned by meansof radially spaced key members 188 and 190. The radial inward endsections of each of the fingers 184 (see FIG. 9) are tapered to providea predetermined clearance between end sections of adjacent fingerswhereby the end sections substantially fully encircle the clamping ring62 during the crimping operation. The plurality of fingers 184 areadapted to collectively engage the outer periphery of the retainer ring62 whereby to provide an applied compressive force to the outerperiphery of the ring 62 which is substantially circumferentiallycontinuous.

In the subject invention, suitable alignment means are provided forlocating the retainer ring 62 concentrically relative to the innerperiphery of the fingers 184. This function is achieved by thesupporting fixture 82, which is located to the left of the crimpingmechanism 104 as viewed in FIG. 8. The fixture 82 is comprised of a base192 fixedly connected to the worktable 88, and a vertically extendingweb 194 which carries a locator plate 196 on an upper surface thereof. Astop element 198 is detachably connected to the right end of the plate196 by a suitable bolt or cap screw 197 and selectively axially spacedvia a washer 200. The element 198 projects upwardly relative to theupper surface of the plate 196 and defines a vertically extendingshoulder which is adapted to locatably receive the open end of the dirtshield 36.

The supporting fixture 82 also functions to laterally coaxially spacethe leveling strut 10 with respect to the central longitudinal axis ofthe mechanism 104. As best seen in FIG. 9, a retaining plate 202 isdisposed along one side of the plate 196 and laterally spaced from thecentral axis of the mechanism 104 a distance conforming to the radius ofthe dirt shield 36. The retaining plate 202 is detachably connected tothe plate 196 by suitable fasteners 204 and in view of accommodating thedirt shields or varying diameters, various spacer or washer elements 206can also be interposed between the plate 202 and an outer lateralsurface of the web 194. It will be noted that since the clamping ring 62has previously been axially located with respect to the dirt shield 36,that by positioning the shield 36 against the stop 198 and plate 202respectively, that the ring 62 will accordingly be precisely positionedwith respect to the crimping fingers 184 whereby the ring 62 can becrimped to fixedly and sealingly secure one end of the diaphragm 44 tothe body member 14.

With reference to FIG. 5, the next step in assembling the combinationshock absorber-leveling unit 10 is to invert the diaphragm 44 and sleevethe end section 56 about the lower end of the dirt shield 36. During theinverting and sleeving step, the shock absorber assembly 12 is retractedrelative to the dirt shield 36 whereby the end cap 16 is abutted orbottomed against the interior surface of the end cap 40. The retracting,inverting and sleeving steps are accomplished by a press or invertingapparatus indicated generally at 210 in FIG. 12.

Generally speaking, the apparatus 210 is comprised of a relativelystationary support structure 212, a vertically displaceable pressassembly 214, and a finger mechanism 216 located below the assembly 214.The support structure 212 includes a base plate 218 which is fixedlymounted via a plurality of bolts, screws or the like 222 to the top of asuitable worktable or the like 220. The plate 218 is connected to avertically extending column of welded construction comprised of a rigidend plate 224, a pair of laterally spaced side walls one of which isindicated at 226, and a plurality of vertically spaced reinforcing beamsor teirs 228. The structure 212 also includes a pair of laterally spacedkeeper blocks 230 which are fixedly connected to the end plate 224 by aplurality of vertically spaced bolts, screws or the like 232. Each ofthe blocks 230 include an inwardly extending lip or flange 234 which isadapted to slidably support or cradle a slide plate 236 of the assembly214.

In the subject apparatus, the press 214 is adapted to be adjustablyconnected at selective vertical positions to the plate 224 whereby topermit the apparatus 210 to be utilized with a wide variety of differingshock absorber-leveling units 10. In this regard the plate 224 isprovided with one or more rows of vertically spaced threaded aperturesor slots 238 which can be selectively utilized to fixedly secure theplates 236 and 224 via insertion of suitable fasteners 240 but whichwill provide some degree of vertical movement without requiring thecomplete removal of the fasteners 240. The slide plate 236 andcorrespondingly the assembly 214 is movably located relative to theapertures 238 in response to rotation of a feed screw 242, the latterbeing threadably connected to an aperture 244 formed in a top plate 246of the assembly 214. The feed screw 242 is rotatably supported in a boreformed in a support block 248, the latter being fixedly connected to theend plate 224 by suitable bolts, screws or the like 250. The feed screw242 is axially immovably supported relative to the block 248 by a pairof vertically spaced nuts 252 and washers 254, the nuts 252 beingnon-rotatably secured to the feed screw 242 by suitable locking pins orthe like 256. The vertically position the press 214 relative to themechanism 216, the bolts 240 are removed and the feed screw 242 isrotated until the bolt holes of the plate 236 are again in registrationwith an aperture 238. The position of the assembly is then fixed byreinsertion of the bolts 240.

The assembly 214 is comprised of a shaft 258 slidably supported in outerhousing 260. The upper end of the shaft 258 is drivingly connected to afluid actuated power cylinder 262, the latter including a stub shaft 264threadably connected to one end of the shaft 258, and having a roll pin266 extending therebetween which is adapted to preclude relativerotational movement. The shaft 258 is guidably supported by the housing260 via a pair of vertically spaced cylindrically shaped bushings 268spaced on opposite ends of a section of tubing 270. The lower end of theshaft 258 carries a clamp member 272 having an aperture 274 adapted todetachably receive an attachment ring adaptor 276, the latter includinga complementary recess 278 for nestingly receiving the upper attachmentring 42 of the combination shock absorber-leveling strut 10.

As indicated above, the press unit 214 is vertically adjustable relativeto the support structure 212 with the unit 214 including means forfurther adjusting the displacement of the shaft 258 to accommodatecombination shock absorber-leveling units 10 of differing dimensions. Inthis regard an elongated rod or shaft 280 is slidably supported in acasing or sleeve member 282 which in turn is connected to an outersurface of the housing 260. The member 282 carries first and secondaxially spaced bushings 284 at opposite ends, and the lower end of therod 280 is threadably connected to the clamp member 272 andnon-rotatably secured thereto by a lock nut 286. The axially opposite orupper end of the rod 280 includes a threaded section 288 for receivingfirst and second lock nuts 290. By axially locating the nuts 290relative to the upper surface of the sleeve 282, it will be seen thatthe downward stroke of the power cylinder can be adjusted relative tothe finger mechanism 216 for accommodation of combination shockabsorber-leveling units 10 of varying axial dimensions.

With reference to FIGS. 12 and 13, the finger mechanism 216 includes aplurality of radially extending, circumferentially spaced finger blocks292 slidably supported in rectangularly shaped grooves 294 formed in anupper surface of an annularly shaped guide plate 296. The blocks 292 aremovably secured in the grooves 294 by a retainer plate 298, the latterbeing connected to the guide plate 296 by a plurality ofcircumferentially spaced bolts, screws or the like 300. A finger element302 is connected at the inner end of each of the blocks by suitablefastener elements 304 and each extends upwardly relative to the uppersurface of the plate 298 whereby to accommodate engagement of theelements 304 within the lower end of the diaphragm 44, as shallhereinafter be explained. The radially outward end of the finger blocks292 are slidably supported on an upper surface of a cam plate 306 whichincludes an inwardly extending flange section 308 which is located in anannularly shaped recess 310 formed at the lower end of the guide plate296. The cam plate 306 is axially supported for rotational movementrelative to the guide plate 296 by a ring shaped retainer element 312which is fixedly connected to a lower surface of the guide plate 296 bya plurality of suitable fastener means 314.

In the subject invention, the finger mechanism 216 is resilientlysupported relative to the worktable 220. In this regard an annularlyshaped support member 316, having an outward radially extending flange318, is connected to the work supporting table 220 via a plurality ofsuitable fasteners 320. The support member 316 also includes an upwardlyextending skirt or sleeve portion 322 which engages a centrally formedopening in the guide plate 296. A plurality of circumferentially spaced,vertically extending coil spring elements 342 are interposed verticallybetween the member 316 and the plate 296, the elements 324 having endportions engageably located in vertically aligned apertures formedrespectively in the plate 296 and member 316. An alignment rod 325 islocated interjacently within each of the spring elements 324 andprovides a stop or limit for downward movement of the mechanism 216. Theupper end of each of the apertures formed in the plate 296 areadjustably closed by threaded set screws or plugs 328, the latterproviding an adjustment means for vertically locating the mechanism 216relative to the press 214 and table 220. Moreover, relative rotationalmovement between the mechanism 216 and the worktable 220 is precluded bya pin and set screw (not shown) located in a slot formed in the skirt orsleeve portion 322 of the member 316.

As best seen in FIG. 13, the plate 306 includes a number ofcircumferentially extending camming slots or recesses 330 and 332 inconformance with the number of finger blocks 292. To radially displacethe blocks 292, one end of each of the slots 330 and 332 are radiallyspaced relative to the vertical axis of the mechanism 216 a greaterdistance than an opposite end. Each of the finger blocks 292 areoperatively connected to the plate 306 by a camming roller 334engageably disposed in one of the camming slots 330 or 332. The rollers334 are connected to the outer end of the finger blocks 292 via athreaded support section 336 which also preferably includes a suitablelubricating fitting 340.

In the subject invention, the finger mechanism 216 is rotated inresponse to reciprocal movement of a fluid actuated cylinder 342, thecylinder 342 including a connecting rod 344 having an outer endconnected to a slide block 346. The block 346 is slidably supportedbetween a pair of laterally spaced keeper plates 348 and 350, andincludes a transversely extending lug or ear section 352 including aninwardly extending camming slot 354. The slot 354 is drivingly engagedby a complementarily formed camming element 356 connected to the lowerend of the cam plate 306. Thus, in response to reciprocal movement ofthe cylinder 342, the cam plate 306 is rotated through an arc conforminggenerally to the circumferential distance between opposite ends of theslots 330 and 332. In accordance therewith, each of the finger blocks292 will be radially displaced outwardly a predetermined distancerelative to the central vertical axis of the mechanism 216 in dependenceon clockwise or counterclockwise rotation respectively.

To operate the apparatus 210 whereby to invert and sleeve the diaphragm44 to the lower end of the dirt shield 36, it will be initially assumedthat each of the finger blocks 292 are inwardly radially locatedrelative to the central vertical axis of the mechanism 216, and that theshaft 250 of the press 214 is in its upper retracted position asillustrated in FIG. 12. Moreover, the combination shockabsorber-leveling unit 10 is further assumed to be pre-assembled inconformance with FIG. 4. To commence the operation, the shock absorber12 is compressed manually, the lower end of the diaphragm 44 istelescopically disposed over each of the finger elements 302, and theupper end cap 40 and attachment ring 42 are nestingly located in therecess 278 of the adaptor 276 at the lower end of the shaft 258. Tofacilitate the above, a suitable guiding or locating means 356 can beprovided which preferably can be fixedly connected to the end plate 224.In response to actuation of the power cylinder 342, the cam plate isrotated counterclockwise to displace the finger elements 292 outwardly.Because of the engagement of the finger elements 302 within the lowerend section 56 of the diaphragm 44, the section 56 will be deformablystretched in an outer direction. With the section 56 of the diaphragm inthe aformentioned condition, the power cylinder 262 of the press 214 isactuated. The initial portion of the stroke of the power cylinder 262results in the lower end of the dirt shield 36 engaging the radiallyexpanded portion of the diaphragm 44 interjacently of each of the fingerelements 302. As the dirt shield 36 continues to be driven downwardly,the end of the diaphragm 44 is peeled or slidably removed from theelements 302 and invertingly repositioned on the lower peripheralsurface of the shield 36. Thus, in accordance with the inverting andsleeving steps, the combination shock absorber-leveling unit 10 willassume the preassembled condition depicted in FIG. 5.

The next step in the assembly of the unit 10 involves axially locatingthe return bend 54 of the diaphragm relative to the end attaching ormounting rings 20 and 42 in accordance with pre-determined dimensionalrelationship therebetween. The process involves placing the unit 10 in alocator fixture and pressurizing the variable volume chamber 46 definedby the dirt shield 36 and the diaphragm 44 whereby to bias the endportion 56 of the diaphragm 44 toward the open end of the dirt shield 36and seat the return bend 54 against a locating shoulder as shallhereinafter be described. The locator fixture for accomplishment of theabove indicated procedure is indicated generally at 360 in FIGS. 14 and15. Generally speaking, the fixture 360 comprises a base plate 362,first and second longitudinally spaced mounting ring receiving blocks364 and 366, and a full encirclement locking device 368 locatedlongitudinally between the blocks 364 and 366.

The base plate 362 is provided with a pair of longitudinally spacedinwardly extending recesses or grooves 370 and 372 which are utilized tocoaxially align the blocks 364 and 366. Toward this end, the block 364is connected to a slide block 374 by a pair of laterally spaced fastenermeans indicated at 376 and 378 respectively. The slide block 374includes a downwardly extending, rectangularly shaped tongue 380 whichcooperatively engages the slot 370. In a like manner, the block 366 isconnected to a second slide block 382 also having a tongue 384 which isdisposed in the slot 372. The receiving blocks 364 and 366 arerespectively adapted to receive either the cap member 18 or mountingring 20 disposed at the lower end of the reserve tube 14 and theattachment ring 42 or end cap 40 disposed at the upper end of the dirtshield 36. To facilitate the above and by way of example assuming therings 20 and 42 are to be accommodated, the block 364 is provided with arecess having inwardly tapered sidewalls which are adapted to nestinglyreceive an outer peripheral surface of the mounting ring 20. On theother hand, the block 366 includes comparable recess 388 also havinginwardly tapered sidewalls which are adapted to receive the outerperipheral surface of the attachment ring 42. In the present fixture360, the location of each of the receiving blocks 364 and 366 islongitudinally adjustable relative to the assembly 368. In this regardthe base plate 362 includes a pair of laterally spaced, longitudinallyelongated passages 390 and 392 each of which includes a counterboredlower section 391 and 393 respectively. The slide block 382 is immovablyconnected to the base plate 362 via a pair of suitable, laterallyspaced, fastener elements 396, the elements 396 being threadably engagedto a square headed nut 394. The distance across the flats of the nutsconforms generally to the width of the lower section 391 and 393 tofacilitate loosening and tightening the elements 396 solely from the topside of the plate 362. Since the receiving block 364 is connected to thebase plate 362 at the opposite longitudinal end thereof in an identicalmanner, the detailed description is omitted for purposes of simplicity.

The locking ring assembly 368 is comprised of upper and lower splitcollar elements 396 and 398 which are pivotably connected at one end bya suitable dowel pin 400. The lower element 396 is fixedly connected tothe base plate 362 by suitable fasteners which are indicated generallyat 402. One end of a laterally extending operating lever is pivotablyconnected to the upper collar element 396 via a pivot pin 397 with anopposite end of the lever 404 being adapted to be nestingly received ina groove or recess 406 formed in a lever retaining block 408 whereby tosecure the elements 396 and 398 in a relatively closed position. On theother hand, the lever 404 can be pivoted out of the recess 406 to permitthe upper element to be pivoted about the pin 400 to facilitate thereceipt of the combination unit 10 in the fixture 360. The retainingblock 408 is fixedly connected to the base plate 362 by a pair ofsuitable bolts, screws or the like 410 which are longitudinally spacedand threaded into suitably formed apertures therein.

In the closed position, the collar rings 396 and 398 form a pair ofcoaxial passages 412 and 414 which define a radially extending shoulder416. The diameter of the passage 413 conforms substantially to thediameter of the reserve tube 14 and the diameter of passage 414 conformsto the diameter of the dirt shield 36 including the sleeved end portionof the diaphragm 44. When the combination shock absorber-leveling unit10 is disposed in the fixture 360, the shoulder 416 is adapted to seator locate the return bend 54 of the diaphragm 44 in response topressurizing the variable volume chamber 46 formed internally of theshield 36 whereby the end portion 56 is slidably displaced relative tothe open end of the shield 36. The introduction of the pressurized mediais accomplished by connecting a suitable source of pressurized fluidsuch as an air hose 417 to the threaded nipple 47 normally utilized tosupport the valve assembly 48.

With the return bend now properly located on the combination shockabsorber-leveling strut 10, the chamber 46 can be depressurized bydisconnecting the fluid source from the threaded nipple 47. As best seenin FIG. 6, the next stop involves locating the clamping ring 58 aroundthe end portion 56 of the diaphragm 44 and fixedly securing the ring 58therearound. In this regard a modified version of the crimping machine80 is provided utilizing a different set of crimping fingers 184 wherebyto accommodate for the larger diameter of the diaphragm 44 sleeved aboutthe shield 36. Moreover, the supporting fixture 82 is also of a modifiedform to facilitate locating the clamping ring 58 relative to thecrimping mechanism 104. In the modified version, the stop element 198 isremoved to permit the dirt shield 36 to be extended axially into thejaws formed by the crimping mechanism 104. For axially locating theclamping ring 58 relative to the jaws of the mechanism 104, a slot orgroove indicated generally at 418 in FIG. 8 is disposed in the uppersurface of the locator plate 196 which is adapted to engageably receivethe threaded nipple 47. Since the modified version of the crimpingmachine and the assembly step for crimping the clamping ring 58 isidentical to the machine 80 and the assembly step described inconjunction with crimping the clamping ring 62, reference may be had tothe prior description and operation for the details thereof.

The remaining steps in the manufacture of the combination shockabsorber-leveling strut 10 involves leak testing of the chamber 46. Inthis regard the unit 10 is preferably located in a test enclosure,wherein the chamber 46 is pressurized to a predetermined test level toensure that the diaphragm 44 is fixedly secured at opposite ends to thereserve tube 14 and the dirt shield 36. During this procedure and as asafety precaution, it is desirable that the same type of screen orpartition be provided between the unit 10 and the individual performingthe test. Thereafter, the strut 10 is preferably submerged in water andair tested whereby to establish the air tightness of the chamber 46.After testing, a predetermined quantity of silicon or other suitableanti-friction lubricant is preferably injected into the chamber 46 toobviate any tendency of adjacent portions of the diaphragm 44 fromadhering together. Thereafter, the valve assembly 58 is connected to thenipple 47, the outer surface of the combination unit 10 is painted andthe individual units are packed in suitable packing cases or cartons,thus completing the manufacturing procedure.

It will be seen from the foregoing that the present invention provides anovel method of assembling a combination shock absorber-leveling strutand includes novel apparatus for performing the various assembly steps.It will be noted that the individual apparatuses and fixtures utilizedin the assembly are each adapted to assure close quality control andminimize to the extreme the number of successive operational steps.Moreover, it will be observed that a new and improved means for sleevingone end of the diaphragm 44 over the dirt shield 36 has been disclosedwhich is rapid, effective and which assures a positive sealingengagement therebetween. Another important advantage of the subjectmethod resides in the manner in which one end of the diaphragm isselectively positioned in response to the introduction of thepressurized media.

While it will be apparent that the exemplary method and apparatus foraccomplishing the method herein described is well calculated to fulfillthe objects above stated, it will be appreciated that the method of thepresent invention, including the apparatus for performing the method areboth susceptible to modification, variation and change without departingfrom the scope of the invention.

I claim:
 1. A method for installing a diaghragm on a combination shock absorber-leveling unit of the type including a shock absorber having a piston and piston rod supported for reciprocal movement in a body member and with a dirt shield connected to the piston rod comprising the steps of:locating the diaphragm on the body member; connecting a first end of the diaphragm to the body member; moving the diaphragm longitudinally to a position wherein the opposite end thereof extends around a plurality of radially movable deforming fingers arranged concentrically of the shock absorber, thereafter moving said fingers radially outwardly and thereby radially expanding a portion of said opposite end of said diaphragm so as to define a generally radially extending portion of said diaphragm, moving said dirt shield and said diaphragm axially of one another so that the adjacent end of said dirt shield engages said radially extending expanded portion of said diaphragm and continuing to move said dirt shield and diaphragm axially of one another such that said end of said dirt shield moves axially interiorly of said fingers and thereby transpositions said opposite end of said diaphragm off from said fingers and onto the end of said dirt shield, and connecting said opposite end of said diaphragm to the dirt shield.
 2. The method as recited in claim 1 wherein said locating step includes gauging the axial location of said diaphragm relative to said unit.
 3. The method as recited in claim 1 which includes the step of locating an attachment ring on said diaphragm.
 4. The method as recited in claim 3 wherein said first mentioned connecting step includes crimping said attachment ring.
 5. The method as recited in claim 1 wherein said inverting step includes forming a return bend in said diaphragm.
 6. The method as recited in claim 5 which includes the step of inflating said diaphragm to selectively axially locate said return bend relative to said unit.
 7. The method as recited in claim 6 which includes the step of limiting axial movement of said unit prior to said inflating step.
 8. The method as recited in claim 1 which includes the step of premounting an attachment ring on said diaphragm.
 9. The method as recited in claim 1 which includes the step of radially expanding said opposite end of the diaphragm prior to said inverting step.
 10. The method as recited in claim 9 which includes the step of driving one end of said dirt shield into said radially expanded portion of said diaphragm.
 11. The method as recited in claim 9 which includes the step of locating one end of said unit in an axially movable apparatus while locating one end of said diaphragm in a radially movable mechanism.
 12. The method as recited in claim 1 wherein said second mentioned connecting step includes locating a second attachment ring on said diaphragm.
 13. The method as recited in claim 12 wherein said second connecting step includes crimping said attachment ring to secure said one end of said diaphragm to said dirt shield.
 14. The method as recited in claim 1 which includes the step of leak testing said diaphragm.
 15. The method as recited in claim 1 which includes the step of injecting a lubricating fluid into said diaphragm. 